AD7730 to interface 10ton load cell with 2mV/V specs

[ex4]

Anybody has tries AD7730 to interface 10ton load cell with 2mV/V specs??
:?::?:
Is it can count to 1 kg resolution without any external amplification ??
thanks in advance

 

[kender]

ad7730 avr

... 10ton load cell with 2mV/V specs??

How many mV/kg does your load cell have?

 

[ex4]

ad7730 code

for my load cell 1uV/kg
can it be done without any external amplifier???
i calculate from the datasheet, that i can get 4 count for 1uV using only that chip

 

[7rots51]

load cell avr

this is c code for AVR for AD7730 ,can be used for other micros by simple changes.

 

[truong_giang2211]

Re: AD7730 for Load Cell

HELLO!CAN U EXPLAIN CLEARLY IN THIS PROGRAM ? I DONT UNDERSTAND ?EX:
this code ?
void ADC_SPI_Init (void)
{
//Set SS high --- Set SS, MOSI and SCK as outputs
SPCR = (1<<SPE) | (1<<MSTR) | (1<<CPHA) | (1<<CPOL) | (1<<SPR0); //Enable SPI in Master mode, mode 3
}
i dont know command code "1<<SPE" ,what is it mean ?

 

[Kurenai_ryu]

have you seen any examples on C coded for AVR??? check the Datasheet!!!!!

SPE is a bit of the SPCR register... as in avr-gcc you can't access individual bits directly... they use the 'bit value' aproach...

some example:

say SU equals to 3 so we mean to turn on only the bit3

we want this REG = 0000 1000 , right?

00001000 binary equals to 8....

which is the relation between 8 and 3 ???? of course power_of_2 !!!!! 2^3 = 8

in binary, there is a more easy approach of power_of_2 ... it's called shifting...

so we shift one bit theree times...

we have 1 bit only:
0000 0001

... and shift it three times!

0000 0010
0000 0100
0000 1000

now we have the 3th bit activated!!!!

the shift operation in C is ..... << ....

so....

REG = 1<<SU ; from my lil' example...



in your case:

SPCR = (1<<SPE) | (1<<MSTR) | (1<<CPHA) | (1<<CPOL) | (1<<SPR0);

means: on the register SPCR, set the bits SPE, MSTR, CPHA, CPOL and SPR0 and clear the rest...

if you don't know wtf does each bit... you must read the datasheet troughfully....